Immobilization of Aspergillus oryzae α-galactosidase in gelatin and its application in removal of flatulence-inducing sugars in soymilk
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Raffinose oligosaccharides (RO) are the major factors responsible for flatulence following ingestion of soybean-derived products. Removal of RO from seeds or soymilk would then have a positive impact on the acceptance of soy-based foods. In this study, α-galactosidase from Aspergillus oryzae was entrapped in gelatin using formaldehyde as the hardener. The immobilization yield was 64.3% under the optimum conditions of immobilization. The immobilized α-galactosidase showed a shift in optimum pH from 4.8 to 5.4 in acetate buffer. The optimum temperature also shifted from 50°C to 57°C compared with soluble enzyme. Immobilized α-galactosidase was used in batch, repeated batch and continuous mode to degrade RO present in soymilk. In the repeated batch, 45% reduction of RO was obtained in the fourth cycle. The performance of immobilized α-galactosidase was tested in a fluidized bed reactor at different flow rates and 86% reduction of RO in soymilk was obtained at 25 ml h−1 flow rate. The study revealed that immobilized α-galactosidase in continuous mode is efficient in reduction of RO present in soymilk.
Keywordsα-Galactosidase Aspergillus oryzae Fluidized bed reactor Gelatin Raffinose oligosaccharides Soymilk
One of the authors Naganagouda V. Kote thanks Gulbarga University, Gulbarga for providing the financial support in the form of University Ph.D. junior research fellowship.
- Barbasgaard, Hansen HP, Diderichsen B (1992) On the safety of Aspergillus oryzae: a review. Appl Microbiol Biotechnol 36:569–572Google Scholar
- Dey PM, Pridham JB (1972) Biochemistry of α-galactosidase. Adv Enzymol 36:911–930Google Scholar
- LeBlanc JG, Silvestroni A, Connes C, Juillard V, Gieri GS, Piard J, Sesma F (2004) Reduction of non-digestible oligosaccharides in soymilk: application of engineered lactic acid bacteria that produce α-galactosidase. Genet Mol Res 3:432–440Google Scholar
- Leske KL, Jevne CJ, Coon CN (1993) Effect of oligosaccharides additions on nitrogen-corrected true metabolizable energy of soy protein concentrate. Poult Sci 72:664–668Google Scholar
- Mulimani VH, Ramalingam (1995) Enzymic hydrolysis of raffinose and stachyose present in soymilk by crude α-galactosidase from Gibberella fujikuroi. Biochem Mol Biol Int 36:897–905Google Scholar
- Steggerda FR, Richard EA, Rackis JJ (1966) Effects of various soybean products on flatulence in the adult man. Proc Soc Exp Biol Med 121:1235–1239Google Scholar
- Suarez FL, Springfield J, Furne JK, Lohrmann TT, Kerr PS, Levitt MD (1999) Gas production in humans ingesting a soybean flour derived from beans naturally low in oligosaccharides. Am J Clin Nutr 69:135–139Google Scholar